http://bugs.winehq.org/show_bug.cgi?id=35954
--- Comment #7 from Anastasius Focht focht@gmx.net --- Hello Rob,
unfortunately there is not much to see from your backtrace and I can't reproduce the crash, runs fine here.
You have to provide a full relay log.
Something like this from your Steam prefix (make sure Steam is _not_ running prior):
--- snip --- $ WINEDEBUG=+tid,+seh,+relay wine ./steam.exe -no-dwrite -applaunch 17470 -windowed >>log.txt 2>&1 --- snip ---
and attach the resulting file to the bug (compress and split if too large).
Regards